p29 pre-pulsar shuttle (or prime) is a period-29 shuttle oscillator discovered by David Buckingham on August 2, 1980, making it the first oscillator of that period to be found. In terms of its 54 cells it is the smallest known period-29 oscillator. The oscillator works by combining the 15-generation, two-tub pre-pulsar shuttle mechanism used in Eureka with a 14-generation pre-pulsar shuttle mechanism. Hassling pre-pulsars in this way was the only known way of constructing period 29 oscillators until the discovery of the p29 traffic-farm hassler. In September 1994 Bill Gosper found that two copies of pre-pulsar shuttle 29 could be used to hassle a pentadecathlon. Gosper used this to construct the p58 toadsucker.
Some variants of this shuttle are shown below. A 42-glider synthesis is known for one variant, 56P29.
A fully symmetric variant of this oscillator was first known to appear semi-naturally in December 2014, in a soup found by Richard Schank using apgsearch.
4 reveals two pre-pulsars (black) being hassled by a 15-generation mechanism (green) and a 14-generation mechanism (red).
A slightly larger version of this oscillator, 56P29, with just one pre-pulsar (black) and an alternate 14-generation stabilization (red)RLE: here
A much larger version of this oscillator with four pre-pulsarsRLE: here
- 54P29.1 at Heinrich Koenig's Game of Life Object Catalogs